The present invention relates to a new and distinct cultivar of Cercis canadensis (redbud) grown as an ornamental tree for home and commercial landscapes. Redbud is typically grown as a small tree for its attractive purple flowers that are borne in the spring, and sometimes for its interesting foliage color (purple, variegated, or golden leaf forms) or architectural form.
The new and distinct cultivar of redbud resulted from a formal breeding program established by the inventors in Raleigh, N.C., United States. One of the objectives of the breeding program was to develop a variegated-leaf form of redbud that exhibited the weeping growth habit. ‘WHITEWATER’ originated as a second-generation descendant from a controlled hybridization of Cercis canadensis cultivars ‘Silver Cloud’ and ‘Covey’ made in spring 1999 in Raleigh, N.C. Established trees of both cultivars growing in a botanical garden in Raleigh, N.C. were used to make the controlled hybridizations. The hybridizations were made in both directions, with each cultivar being used as both a seed and pollen parent. Fruit pods and seed were obtained on both the ‘Covey’ and ‘Silver Cloud’ trees. ‘Covey’ (U.S. Plant Pat. No. 10,328) was introduced in Madison, Ohio in 1997 and is described as a green leafed, weeping form of Cercis canadensis with light purple flowers. ‘Silver Cloud’ (non-patented) is a non-weeping, variegated-leaf form of eastern redbud (Cercis canadensis) introduced in 1964 in Crestwood, Ky. Both cultivars are commonly available in commerce.
The first generation seeds resulting from the spring 1999 hybridization were harvested in fall of 1999 and germinated in a greenhouse in Raleigh, N.C. in the winter of 2000. Three seedlings, designated NC99-18-1, NC99-18-2, NC99-18-3, were obtained from the ‘Covey’ seed parent, and one seedling, designated NC99-18-4, was obtained from the ‘Silver Cloud’ seed parent. These resulting 4 first generation seedlings were grown in a greenhouse in year 2000, and subsequently planted together in a field setting at a research station, isolated from other redbuds, in spring 2001. All four of these first generation seedlings (NC99-18-1, NC99-18-2, NC99-18-3, and NC99-18-4) showed green leaves and normal (non-weeping) growth habit. These trees flowered and set fruit in spring 2005, and the second generation seed was collected and bulked that same year off of all 4 trees. This bulked seed was germinated in a greenhouse in Raleigh, N.C. in December, 2005. From these approximately 1600 seedlings, 102 seedlings showing green and white variegated leaves and weeping growth habit were selected and grown in the greenhouse in spring and summer, 2006. These 102 seedlings were later transplanted to the field in November, 2006, and one tree, later designated ‘WHITEWATER’, was selected in summer 2007 as the best individual for its green and white variegated leaf color and weeping growth habit. This original tree demonstrated characteristics identical to those subsequently expressed on other trees when propagated by chip budding. This single tree is the subject of the present invention ‘WHITEWATER’.
The distinguishing traits of ‘WHITEWATER’ are its distinctive green and white variegated leaves, and its weeping growth habit. The cultural requirements for ‘WHITEWATER’ are well-drained soil, full sun to partial shade, and moderate moisture. ‘WHITEWATER’ exhibits no serious pest or disease problems known to the inventors.
The closest comparisons known to the inventors are its grandparents, ‘Silver Cloud’ and ‘Covey’. In direct comparisons of ‘WHITEWATER’ with the 2 grandparent cultivars in the inventor's experimental trials, trees of ‘WHITEWATER’ are weeping in growth, compared to the non-weeping growth of ‘Silver Cloud’. ‘WHITEWATER’ differs from the ‘Covey’ grandparent in having variegated leaves. ‘WHITEWATER’ is clearly distinct from its original grandparents. Two other weeping architecture redbuds currently in the trade, ‘Traveller’ (U.S. Plant Pat. No. 8,640) and ‘Cascading Hearts’ (U.S. Plant Pat. No. 18,528), have entirely green leaves, unlike the variegated leaves of ‘WHITEWATER’. ‘WHITEWATER’ differs from its parents (NC99-18-1, NC99-18-2, NC99-18-3, and NC99-18-4). Because seed were bulked from all 4 first-generation trees, it is impossible to say with certainty which specific parental selection ‘WHITEWATER’ was actually derived from. However, all 4 parental selections showed entirely green leaves and non-weeping architecture, distinctly different from ‘WHITEWATER’, which shows variegated leaves and weeping growth habit.
The first asexual propagation of ‘WHITEWATER’ was conducted by Alex and Harald Neubauer on behalf of the inventors in fall 2007 in Belvidere, Tenn. ‘WHITEWATER’ has subsequently been propagated in the same location in 2008. In all cases, the original tree was propagated asexually by chip budding in late summer onto Cercis canadensis rootstock. Such budded trees heal rapidly, and resume normal growth the following spring after budding. Two trees derived from chip budding of the cultivar were established in the inventor's test plots in January 2009. During all asexual propagation, the characteristics of the original tree have been maintained. Trees derived from chip budding exhibit characteristics identical to those of the original tree, and no aberrant phenotypes have appeared.
Performance evaluation of the original tree and budded trees demonstrate this cultivar to be relatively consistent in its characteristics even under the different growing conditions associated with yearly climatic variation.
Trees of the new cultivar are moderately vigorous after chip budding in the nursery setting, growing up to 1.2 meters the following growing season after fall budding. Trees are weeping in growth habit. ‘WHITEWATER’ produces light purple flowers in early spring.
‘WHITEWATER’ is distinguished from other related known cultivars based on the unique combination of traits including weeping growth habit and green and white variegated leaf color.
The new cultivar has been named the ‘WHITEWATER’ cultivar. No public sale of ‘WHITEWATER’ has yet taken place at the time of this application.